<?php

namespace App\Livewire\Schedule;

use App\Models\User;
use App\Models\Dish;
use App\Models\Schedule;
use App\Models\ScheduledUserDish;
use Carbon\Carbon;
use Livewire\Component;

class ScheduleGenerator extends Component
{
    public $selectedMonth;
    public $selectedYear;
    public $selectedUsers = [];
    public $clearExisting = true;
    public $showAdvancedOptions = false;
    public $isGenerating = false;
    
    public function mount()
    {
        $this->selectedMonth = now()->month;
        $this->selectedYear = now()->year;
        
        // Select all users by default
        $this->selectedUsers = User::where('planner_id', auth()->id())
            ->pluck('id')
            ->toArray();
    }

    public function render()
    {
        $users = User::where('planner_id', auth()->id())
            ->orderBy('name')
            ->get();
            
        $months = [
            1 => 'January', 2 => 'February', 3 => 'March', 4 => 'April',
            5 => 'May', 6 => 'June', 7 => 'July', 8 => 'August',
            9 => 'September', 10 => 'October', 11 => 'November', 12 => 'December'
        ];
        
        $years = range(now()->year - 1, now()->year + 2);
        
        return view('livewire.schedule.schedule-generator', [
            'users' => $users,
            'months' => $months,
            'years' => $years
        ]);
    }

    public function generate()
    {
        $this->validate([
            'selectedUsers' => 'required|array|min:1',
            'selectedMonth' => 'required|integer|min:1|max:12',
            'selectedYear' => 'required|integer|min:2020|max:2030',
        ]);

        $this->isGenerating = true;

        try {
            $startDate = Carbon::createFromDate($this->selectedYear, $this->selectedMonth, 1);
            $endDate = $startDate->copy()->endOfMonth();
            
            // Clear existing schedule if requested
            if ($this->clearExisting) {
                ScheduledUserDish::whereBetween('date', [$startDate, $endDate])
                    ->whereIn('user_id', $this->selectedUsers)
                    ->delete();
            }

            // Get all dishes assigned to selected users
            $userDishes = [];
            foreach ($this->selectedUsers as $userId) {
                $user = User::find($userId);
                $dishes = $user->dishes()->get();
                
                if ($dishes->isNotEmpty()) {
                    $userDishes[$userId] = $dishes->toArray();
                }
            }

            // Generate schedule for each day
            $currentDate = $startDate->copy();
            while ($currentDate <= $endDate) {
                foreach ($this->selectedUsers as $userId) {
                    // Skip if user already has a dish for this day
                    if (ScheduledUserDish::where('date', $currentDate->format('Y-m-d'))
                            ->where('user_id', $userId)
                            ->exists()) {
                        continue;
                    }

                    // Get available dishes for this user
                    if (!isset($userDishes[$userId]) || empty($userDishes[$userId])) {
                        continue;
                    }

                    $availableDishes = $userDishes[$userId];
                    
                    // Simple random assignment (you can implement more complex logic here)
                    if (!empty($availableDishes)) {
                        $randomDish = $availableDishes[array_rand($availableDishes)];
                        
                        ScheduledUserDish::create([
                            'user_id' => $userId,
                            'dish_id' => $randomDish['id'],
                            'date' => $currentDate->format('Y-m-d'),
                            'planner_id' => auth()->id(),
                        ]);
                    }
                }
                
                $currentDate->addDay();
            }

            $this->isGenerating = false;
            
            // Emit event to refresh calendar
            $this->dispatch('schedule-generated');
            
            session()->flash('success', 'Schedule generated successfully for ' . 
                $this->getSelectedMonthName() . ' ' . $this->selectedYear);
            
        } catch (\Exception $e) {
            $this->isGenerating = false;
            session()->flash('error', 'Error generating schedule: ' . $e->getMessage());
        }
    }

    public function regenerateForDate($date)
    {
        try {
            // Clear existing assignments for this date
            ScheduledUserDish::whereDate('date', $date)
                ->whereIn('user_id', $this->selectedUsers)
                ->delete();
            
            // Regenerate for this specific date
            $currentDate = Carbon::parse($date);
            
            foreach ($this->selectedUsers as $userId) {
                $user = User::find($userId);
                $dishes = $user->dishes()->get();
                
                if ($dishes->isNotEmpty()) {
                    $randomDish = $dishes->random();
                    
                    ScheduledUserDish::create([
                        'user_id' => $userId,
                        'dish_id' => $randomDish->id,
                        'date' => $currentDate->format('Y-m-d'),
                        'planner_id' => auth()->id(),
                    ]);
                }
            }
            
            $this->dispatch('schedule-generated');
            session()->flash('success', 'Schedule regenerated for ' . $currentDate->format('M d, Y'));
            
        } catch (\Exception $e) {
            session()->flash('error', 'Error regenerating schedule: ' . $e->getMessage());
        }
    }

    public function clearMonth()
    {
        try {
            $startDate = Carbon::createFromDate($this->selectedYear, $this->selectedMonth, 1);
            $endDate = $startDate->copy()->endOfMonth();
            
            ScheduledUserDish::whereBetween('date', [$startDate, $endDate])
                ->whereIn('user_id', $this->selectedUsers)
                ->delete();
            
            $this->dispatch('schedule-generated');
            session()->flash('success', 'Schedule cleared for ' . 
                $this->getSelectedMonthName() . ' ' . $this->selectedYear);
                
        } catch (\Exception $e) {
            session()->flash('error', 'Error clearing schedule: ' . $e->getMessage());
        }
    }

    public function toggleAdvancedOptions()
    {
        $this->showAdvancedOptions = !$this->showAdvancedOptions;
    }

    private function getSelectedMonthName()
    {
        $months = [
            1 => 'January', 2 => 'February', 3 => 'March', 4 => 'April',
            5 => 'May', 6 => 'June', 7 => 'July', 8 => 'August',
            9 => 'September', 10 => 'October', 11 => 'November', 12 => 'December'
        ];
        
        return $months[$this->selectedMonth];
    }
}